Device for manipulating a stylet unit

ABSTRACT

A device for manipulating a stylet unit for positioning a electrode cable in a body cavity has a handle supporting, at a distal portion thereof, a rotatable bracket member. A slide member carrying a screw for fixation of a proximal contact element of the electrode cable is displaceably mounted on the bracket member so as to be adjustable to variations in length of a central lumen of the electrode cable, into which the stylet unit is to be inserted.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to a device for manipulating astylet for positioning an electrode cable in a body cavity, such as ahuman heart. More particularly, the present invention relates to adevice for manipulating a stylet unit of the type having a stylet sleeveand a guide wire located within the sleeve. The distal end portion ofthe inner guide wire is pre-shaped into a curved configuration so thatwhen it is freely exposed from the distal end portion of the associatedflexible, but stiffer stylet sleeve by performing a relativedisplacement between the latter and the guide wire, the free distal endportion of the guide wire will be capable of bending the distal endportion of the electrode cable into a desired curved shape. In thismanner, the tip of the electrode cable may be bent between asubstantially straight configuration to a substantially J-shapedconfiguration in order to locate and fixate the tip of the electrodecable at a suitable site in the heart.

2. Description of the Prior Art

U.S. Pat. No. 5,170,787 discloses a device for manipulating a styletunit of the kind referred to above for in vivo positioning of anelectrode cable. This known device has a handle having a first handlemember and a second handle member attached to one another for mutualmovements thereof, one of the handle members being connected to aproximal end portion of one of the stylet sleeve and guide wire, theother of said handle members being connected to a proximal end portionof the other of the stylet sleeve and guide wire. This device furtherhas means attached to a distal end portion of one of the first andsecond handle members for fixation of a proximal contact element of theelectrode cable to that one of the first and second handle members. Sucha prior art device normally operates smoothly and flawlessly withelectrode cables having substantially the same length of the centrallumen into which the stylet unit is to be inserted. Thus, in order toobtain proper function of the device, e.g. to ensure accurate control ofthe electrode tip while positioning the same in e.g. a heart, it isimportant that the distal tip of the guide wire always reaches thebottom end of the lumen, while the proximal contact element of theelectrode cable is fixated to its associated handle member of thedevice. Although the overall outer length of the electrode cables may besubstantially identical, the length of their inner central lumen mayvary in dependence of the actual electrode tip design being used, e.g.active (screw-in) or passive fixation (fins or tines). Alsomanufacturing tolerances of some models of the electrode cables may varywithin the range ±1.3 cm. In the preferred embodiment of the styletmanipulating device of U.S. Pat. No. 5,170,787, the distance between thedistal end of the guide wire and the point of fixation of the proximalelement of the electrode cable to the associated one of the handlemembers should be a fixed distance, i.e. the associated handle membershould be a stationary handle member to which the guide wire isattached, and the other handle member should be a displaceable handlemember to which the stylet sleeve is attached. Such a known fixedlength-manipulating device therefore is not suitable for accuratehandling of the tip of the electrode cables having various lengths ofthe lumen thereof.

In order to modify existing stylet manipulating devices of theabove-mentioned type so as to accommodate lumen length variations andmanufacturing tolerances, it has been suggested (see “846/ResearchDisclosure. July 1998, publication 41106”) to provide a set of adaptersof various lengths (FIGS. 2 and 3) which are detachably mountable to oneand the same handle unit. These adapters are made to fit variouspredetermined electrode lumen lengths. Furthermore, FIG. 4 of thispublication “41106” indicates the use of a telescopic adapter assemblyto accommodate lumen length variations by means of one singlehandle/stylet unit. Such a telescopic assembly requires rathercomplicated and expensive structural means in order to obtain accurateand stable length adjustments and to prevent mutual rotation of thetelescopic elements.

SUMMARY OF THE INVENTION

It is an object of the present invention to eliminate the aforementionedshort-comings of the prior art devices and to provide a simplifiedstylet manipulating device, which has one single stylet/handle unitwhich can be used for manipulations of electrode cables having variouslumen lengths.

The above object is achieved in accordance with the principles of thepresent invention in a device for manipulating a stylet unit wherein thestylet unit has a stylet sleeve and a guide wire located in the sleeve,the device having a handle with a first handle member and a secondhandle member attached to each other for movement relative to eachother, one of said handle members being connected to a proximal end ofone of the stylet sleeve and guide wire, and the other of the handlemembers being connected to a proximal end of the other of the styletsleeve and guide wire, a fixation arrangement attached to a distal endof one of the first and second handle members for fixing a proximalcontact element of the electrode cable to the handle member to which itis attached, the fixation arrangement being displaceably mountedrelative to the handle member to which it is attached so as to beadjustable to accommodate variations in length of a central elongatedlumen of the electrode cable into which the stylet unit is to beinserted, and wherein the fixation arrangement has a slide memberslidably mounted in a single bracket member having a proximal baseportion rotatably attached to the handle member to which the fixationelement is attached, and a distal shaft portion with a guide track forthe slide member, the slide member carrying a locking mechanism forsecuring the proximal contact element of the electrode cable to theslide member.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a first embodiment of a stylet manipulatingdevice of the present invention.

FIG. 2 is an exploded perspective view of a bracket and a slidablefixation means of the device in FIG. 1.

FIG. 3 is a perspective view of the bracket and the slidable fixationmeans in FIG. 2 in the assembled state.

FIG. 4 is an exploded perspective view of an alternative embodiment of abracket and a slide assembly of a stylet-manipulating device of thepresent invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a device 10 of the present invention for manipulatinga stylet unit 12 consisting of a tubular stylet sleeve and a guide wirelocated within the sleeve, for positioning of an electrode cable in abody cavity, such as a heart. The device 10 has a handle 14 to behand-held by an operator during implantation of the electrode cable. Theproximal or rear end of the guide wire is fixated in the rear part ofthe handle 14 and extends forwardly through a first stationary guidetube 16 and through a second guide tube 18 which is attached to a styletsleeve maneuvering element 20 and telescopically slidable within thefirst guide tube 16 when the maneuvering element 20 is pushed back andforth by the thumb and the index finger of the operator. The proximal orrear end of the stylet sleeve is secured to the inside of the secondguide tube 16 for movement together therewith. The stylet unit 12, i.e.the stylet sleeve and the guide wire, extends further forwardly througha central passage 22 in a bracket member 24 which is rotatably attachedto the distal end portion of the handle 14, and through a passage 26 ina slide member 28 for fixation of a proximal contact element of theelectrode cable to be connected to the manipulating device 10.

In a free state, i.e. when the stylet sleeve is retracted rearwardly,the distal end portion (not shown) of the guide wire of the stylet unit12 has a pre-shaped curved configuration so as to be able to—in a knownmanner—bend the distal end of the electrode cable into a desired curvedconfiguration, such as a J-shape, when the stylet unit 12 is fullyinserted to the bottom of the central lumen of the electrode cable.

In order to adapt the manipulating device 10 to different electrodecables respectively having different lengths of the central lumen, i.e.to make it possible to adjust the longitudinal position of the fixationof the proximal contact element of the electrode cable to the handle 14,while holding the distal end of the guide wire against the bottom of theelectrode lumen, the fixation slide member 28 is longitudinally slidablein the bracket member 24 and securable in a desired position therein. Asshown in FIGS. 1-3, in the preferred embodiment of the invention thebracket member 24 has a proximal base portion 30 which is rotatablyattached to the distal end of the handle 14, and a distal shaft portion31 having a substantially U-shaped cross-section with parallel andinwardly directed flanges 32-34 for guidance of the fixation slidemember 28 along the shaft portion 31. The slide member 28 has a bodyportion 36 has opposite side walls on which guide tracks or grooves38,40, are respectively formed, that are complementary with the flanges32,34, respectively, on the shaft portion 31. A threaded bore 41,extending from a top wall of the body portion 36 into the passage 26, isadapted to receive a screw 44 for fixation of the proximal contactelement of the electrode cable to the slide member 28. The slide member28 in its turn is lockable to the shall portion 31 by a locking knob 42formed integrally with the body portion 36 and spring-biasedtransversely towards the flange 32 such that one or more lugs (notshown) on the knob 42 may be brought into locking engagement with atoothed rim 45 on the flange 32 at a desired position along the shaftportion 31. The slide member 28 may be released from its locked positionby pressing the knob 42 towards the body portion 36.

Instead of having interlocking lugs and teeth, the slide member 28 maybe held in a suitable position on the bracket member 24 by frictionalengagement between these components, or by a separate lock screw (notshown) clamping the slide member to the shaft portion.

A second embodiment of the bracket and slide member assembly of themanipulating device of the present invention is shown in FIG. 4. Incontrast to the first embodiment in FIGS. 1-3, the shaft portion 31′ ofthe bracket member 24′ has a tubular shape, and a cylindrical slidemember 28′ fits slidably in the tubular shaft portion 31′. The slidemember 28′ has a central passage for the penetration of the stylet unit12, and a widened distal orifice 46 for receiving the proximal contactelement of the electrode cable. A screw 44′ is adapted to extendradially through an elongate axial slot 48 in the shaft portion 31′ andinto engagement with a threaded bore 41′ in the cylindrical slide member28′ such that the screw 44′ is capable of fixating the proximal contactelement of an electrode cable in the orifice 46 as well as locking theslide member 28′ in a desired position in the shaft portion 31′ byexpanding flexible parts of the slide member 28′ by further tighteningof the screw 44′.

Although modifications and changes may be suggested by those skilled inthe art, it is the intention of the inventors to embody within thepatent warranted hereon all changes and modifications as reasonably andproperly come within the scope of their contribution to the art.

What is claimed is:
 1. A device for manipulating a stylet unit having astylet sleeve and a stylet guide wire disposed within the stylet sleeve,for positioning an electrode cable in a body cavity, said electrodecable having a central elongated lumen into which the stylet unit is tobe inserted, said device comprising: a handle having a first handlemember and a second handle member attached to each another for relativemovements thereof, said handle members respectively being connected torespective proximal ends of said stylet sleeve and said stylet guidewire; a fixation arrangement attached to a distal portion of one of saidhandle members adapted for fixing a proximal contact element of the saidelectrode cable to said one of the said handle members, said fixationarrangement being displaceably mounted relative to said one of saidhandle members so as to be adjustable to accommodate variations inlength of said central elongated lumen of said electrode cable; and saidfixation arrangement comprising a slide member slidably mounted in asingle bracket member having a proximal base portion rotatably attachedto said one of said handle members, and a distal shaft portion having aguide track for said slide member, said slide member carrying a lockingmechanism adapted for securing said proximal contact element of saidelectrode cable to said slide member.
 2. A device as claimed in claim 1wherein said shaft portion of said bracket member has a substantiallyU-shaped cross-section with inwardly directed flanges.
 3. A device asclaimed in claim 2 wherein said slide member has grooves that arecomplementary with said flanges of said bracket shaft portion.
 4. Adevice as claimed in claim 2 wherein said locking mechanism locks saidslide member to said bracket member by frictional engagement betweensaid slide member and said bracket member.
 5. A device as claimed inclaim 4 wherein said slide member has flexible portions which exerttransversely directed biasing forces on said bracket shaft portion.
 6. Adevice as claimed in claim 5 wherein one of said flexible portions hasat least one locking protrusion thereon engageable with ratchet teeth onone of said flanges of said distal shaft portion.
 7. A device as claimedin claim 2 wherein said locking mechanism locks said slide member tosaid bracket member by a ratchet mechanism.
 8. A device as claimed inclaim 7 wherein said slide member has flexible portions which exerttransversely directed biasing forces on said bracket shaft portion.
 9. Adevice as claimed in claim 8 wherein one of said flexible portions hasat least one locking protrusion thereon engageable with ratchet teeth onone of said flanges of said distal shaft portion.
 10. A device asclaimed in claim 1 wherein said shaft portion of said bracket member istubular and has a longitudinal slot for receiving said lockingmechanism, said locking mechanism being slidable within said tubularshaft portion.